N,N-dicyclopropyl-4-(1,5-dimethyl-1H-pyrazol-3-ylamino)-6-ethyl-1-methyl-1,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-7-carboxamide, has the structure of formula I:

Compound I, compositions comprising Compound I, and methods of using Compound I are disclosed in U.S. Pat. No. 8,202,881 B2, which is assigned to the present assignee and is incorporated herein by reference in its entirety.
Typically, in the preparation of a pharmaceutical composition, a form of the active ingredient is sought which has the desired solubility and bioavailability and has sufficient stability that it does not convert during manufacture or storage of the pharmaceutical composition to a different form having different solubility and/or bioavailability. A form of Compound I is desired having properties and stability that allow the preparation of pharmaceutical compositions suitable for the treatment of diseases such as cancer. It has been found through extensive investigation that the form disclosed in this application is the most desirable identified to date with regard to chemical/physical stability, reproducibility and hygroscopicity.